The Sub Membrane Ventilation system works on the same principle as a sub slab ventilation system but is used when a house has a dirt crawl space.
A radon reduction barrier is installed over the dirt floor to create an air tight barrier between the soil and the airspace in the crawlspace. Typically, the material used is a cross woven, laminated polyethylene or EPDM membrane. This material is installed on top of the soil and sealed to the perimeter walls, then a suction point is installed through the barrier to depressurize the soil, and then allow the radon gas to be safely vented out of the house through the installed piping, mitigation fan, discharge pipe etc.
There are situations where a home has both a concrete slab and also a crawlspace, in these cases both areas can and should be mitigated. Depending on the home’s layout there is the possibility that both areas may be connected together with the use of one mitigation fan.
As with both types of systems there may be other options for the location of the mitigation fan and discharge pipe. Please contact your professional at Radon Defense to discuss these options. Contact Us
Cosmetic upgrades such as Fan Covers, Low profile fans and discharge pipe upgrades are available to help the Radon Reduction system blend better into the homes exterior.